Electrical-circuit protector.



No. 800,830. PATENTED OCT. 3, 1905. C. A. ROLPE.

ELECTRICAL CIRCUIT PROTECTOR.

APPLICATION FILED SEPT. 25, 1903. RENEWED JULY 30, 1904.

. UNITED STATES PATENT OFFICE.

CHARLES A. ROLFE, OF ADRIAN, MiCHlGAN, ASSIGNOR, BY MESNE ASSIGNMENTS, TO ROLFE ELECTRIC CO., OF ROCHESTER, NE YORK, A CORPORATION OF NE YORK.

ELECTRICAL-CIRCUIT PROTECTOR.

Specification of Letters Patent.

Patented Oct. 3, 1905.

T0 at whom it may concern/.-

Be it known that I, CHARLEs A. ROLFE, a citizen of theUnited States, residing atAdrian, in the county of Lenawee and State of Miehigan, have invented a certain new and useful Improvement in Electrical-Circuit Protectors, of which the following'is a full, clear, concise, and exact description, reference being had to the accompanying drawings, forming a part of this specification.

My invention relates to electrical circuit protectors for protecting electrical circuits and instruments from the injurious effects of unduly-strong currents.

The prominent objects of my invention are to provide a simple, inexpensive, and practical device of this character to render it unnecessary to make any repairs or undergo any expense in connection with the apparatus after it has been operated by the passage of an unduly-strong current, to simplify and cheapen its construction as much as possible, and to accomplish the foregoing and other desirable results in a simple and expeditious manner.

In the accompanying drawings, Figure 1 is a side elevation of a protective device embodying my present invention. Fig. 2 is a View taken on line 2 2 in Fig. 1. Fig. 2 is a cross-section taken on line 2 2 in Fig. 2. Fig. 3 is a view, partly in elevation and partly in vertical section, of a modified form of de-- vice. Fig. A is a view taken on line A at in Fig. 3. Fig. 5 1s a view taken on line 5 5 1n Fig. 3.

Referring first to the device shown in Figs. 1, 2, and 2, A is anycommon or desirable form of insulating-base, made of wood, porcelain, rubber, or the like. On this are mounted two springs 1 and 2, secured to the base A by means of binding-posts 8 3. A heat-cartridge 4 is mounted upon and supported by the springs 1 and 2. Each of the springs 1 and 2 is forked, as shown in Fig. 2, and the heatcartridge is provided with circular lugs or ears 5 5, by which the forked ends of the springs are engaged, the cartridge being thus readily removable from the springs. The spring 2 is made in two parts or sections, the upper one, 2, of which is hinged to the lower part or section. A small quantity of solder 6-, Fig. 2, is introduced into this hinged connection and serves when it is hard to hold the two sections of the spring rigid with reference to one another. A small spring 7 is secured to the lower section of the spring 2and is arranged to act outwardly upon the upper section 2.

The heat-cartridge 4 consists of a graphite block or pencil secured to two caps 8 and 9, which latter are provided with the lugs or ears 5 5.

The operation of the device thus described is as follows: Under normal circumstances the device is in the condition shown in Fig. 1. Then an u nduly-strong current traverses the circuit, however, the graphite stick of the cartridgea becomes heated and the caps 8 and 9 also become heated and the latter heats the upper section 2 of the spring 2, which in turn heats the small quantity of solder 6 in the hinged joint of this spring. As a result the spring 2 springs out-that is, in a direction away from the other spring-by reason of the loosened connection between its two sections. This breaks the circuit between the end of the spring 2 and the cap 9 of the cartridge, thereby opening the line and relieving the circuit of the unduly-strong current. \Vhen the spring 2 has become freed from the cap 9, the spring 7 will operate to move or swing the upper section 2 of said spring out into normal position-that is, straight with the other section of the spring'and in this normal condition the solder 6 will harden, thereby holding the two sections rigid with one another. The device is reset by reengaging the upper end of the section 2 with the cap 9.

The modification shown in 3 has an insulating-base A and the springs 1 and 2, as in the other arrangement. The spring 2. however, instead of being hinged is provided at its upper end with a star-wheel 2", whichis arranged to rotate, and a small quantity of solder 6, Fig. 5, is provided in the upper end of the spring-arm, so as to rest against the starwheel. The heat-cartridge 1 of this modiiication consists of two metallic caps 8 and 9, provided with the lugs or ears 5 5, one of the same, 9, being provided with alongitudinallyextending pin or spindle 10, whose end is screw-threaded and fits into a threaded insulating-bushing 11 in the cap 8. A coil of wire 12 is arranged about the spindle 10, and an insulating-sleeve 13 is arranged about the coil of wire 12. One end of the wire of the coil 12 is connected with the cap 9 and the other end with the cap 8, whereby connection is made between the springs l and 2 through the coil of wire 12.

The device thus described operates as follows: Under normal conditions it is as shown in Fig. 3. An unduly strong current, however, will cause the coil 12 to become heated and this in turn will heat the cap 9, star-wheel 2", and solder 6. The latter on becoming softened will release the star-wheel and permit the same to turn, whereupon the spring will fly outwardly, thereby breaking the circuit between the star-wheel and the cap 9 and relieving the circuit of the unduly-strong current. The solder upon hardening will hold the star-wheel rigid in the position to which it was turned by the outward movement of the spring. The device can be placed in position again by simply movingthe spring2 inwardly, so thatanother of the prongs of the star-wheel 2 engages the ear 5.

It will be seen that by myinvention Imalie it possible to construct the simplest possible form of heat-coil without any moving or detachable parts. The cartridge itself is simply a heat-concentrating device with suitable means for engaging the ends of the springs. It will also be seen that after each operation the device is automatically resoldered or selfsoldered by the hardening of the solder connected with the movable part which engages one end of the heat-cartridge. In the form of device shown in Fig. 1 a movable part on the spring is restored to its original condition, whereas in the other form of device there is no restoration of any movable part to its original condition, the device being put into condition for another operation by the bringing of another prong or tooth in the star-wheel into position to engage the heat-cartridge. In

each case, however, the self-soldering parts are carried by one of the springs, which may be said to be the circuit governing or controling means or part of the apparatus, in contradistinction to the heat-concentrating means embodied in or forming a part of the heatcartridge.

Itwill be understood that changes and modifications can be made in the apparatus herein set forth without departing from the spirit of my invention.

What I claim is- 1. In an electrical-circuit protector,the combination of a heat-concentrating device, and means for controlling the circuit having provisions for automatically restoring itself to operative condition.

2. In an electrical-circuit protector, the combination of a heat -generating device, and spring means for controlling the circuit, said spring means having provisions whereby it is automatically resoldered in operative condition.

3. In an electrical-circuit protector, the combination of a heat-cartridge containing in its construction a heat concentrating device, spring means for controlling the circuit operating in conjunction with said heat-cartridge, said spring means having a solder-secured joint normally holding it in engagement with the heat-cartridge. but releasing it when melted or softened, substantially as described.

4. In an electrical-circuit protector,the combination of a heat-cartridge comprising a heatgenerating device, a pair of spring-arms supporting said heat-cartridge and engaging the same, one of said spring-arms being provided with a movable member held normally in position by a softenable material, substantially as described.

5. In an electrical-circuit protector,the combination of a heat-cartridge comprising a heatgenerating device, a pair of spring-arms supporting said heat-cartridge and engaging the same, one of said spring-arms being provided with a movable member held normally in po sition by solder, substantially as described.

6. In an electrical-circuit protector,the combination of a heat-cartridge comprising a heat generating device, and a pair of swing-arms supporting and engaging said device, one of said spring-arms being provided with a pivoted member adapted to engage the heat-cartridge and held normally rigid with the springarm by solder, substantially as described.

7. In an electrical-circuit proteetor,the combination of a heat-cartridge comprising a heatconcentrating member and a pair of metallic caps at the ends of the cartridge, each of said caps being provided with ears or lugs, a pair of spring-arms supporting and engaging said cartridge, each of said arms being forked at its upper end to engage the ears on said cartridge, a pivoted member carried by one of said spring-arms, a small quantity of solder engaging and holding said pivoted member normally rigid with the spring-arm carrying it, and means for restoring said member to normal position, substantially as described.

8. In an apparatus of the class specilied, thermally-operable circuit-controlling means having provisions for automatically restoring themselves to operative condition.

9. In an apparatus of the class specilied, a line-spring provided with a releasable engaging device, and having provisions for automatically resoldering said device after release.

10. In apparatus of the class specilied, a jointed line-spring having provisions for antomatically resoldering said joint al'ter release.

11. In apparatus of the class specified, a line-spring constructed with a solder-secu red joint in combination with a spring acting upon one of the parts of said joint to restore the same to operative position.

12. An electrical-circuit protector, comprising thermally-operable securing means normally holding the protector against operation, and circuit-controlling instrumentalities cooperating with said securing means and having provisions whereby they are automatically restored to operative condition.

13. An electrical circuit protector, comprising thermally-operable securing means normally holding the protector against operation, and circuit-controlling instrumentalities cooperating with said securing means and having provisions whereby they are autovmatically reset and resecured in reset condition.

14. An electrical-circuit protector comprising securing means normally holding the protector against operation, and circuit-controlling instrumentalities cooperating with said securing means, and having provisions whereby they are automatically resoldered after operation preparatory for another operation.

15. An electrical circuit protector, comprising securing means normally holding the protector against operation, and circuit-controlling instrumentalities having provisions prising a heat-cartridge, and a jointed circuit.

controlling spring cooperating therewith and having provisions for automatically resoldering itself in operative condition.

In witness whereof I hereunto subscribemy name this 2d day of September, A. D. 1903.

CHARLES A. ROLFE. itnesses:

A. MILLER BELFIELD, I. (1. LEE. 

